The recent past has shown an upsurge in the use of peroxide-based explosives. Terrorist organizations, in particular, have shown an affinity for the use of such explosives, as they can be made from relatively easily obtained components and are simple and inexpensive to fabricate. The 2005 attacks on the London transit system, for example, used peroxide-based explosives. The attempted bombing of a Northwest Airlines airliner in 2009 used a TATP (triacetone triperoxide) explosive. As peroxide-based explosives do not normally include nitro groups, do not exhibit UV absorbance or fluorescence and do not provide easy ionization, many conventional tests for explosive components cannot be used for their detection. Accordingly there is an increased need for methods and systems for providing fast and accurate testing for the presence of such compounds, and especially for such testers that can be used in a field environment.
U.S. Pat. No. 6,767,717 of Jul. 27, 1994 to Itzhaky et al is directed to a method for detecting peroxide-based explosives which comprises dissolving a sample of the material to be tested in a suitable organic solvent, contacting the solution with a solution of a strong acid to release hydrogen peroxide, and contacting the resulting mixture with a peroxidase enzyme, a buffer and a substrate capable of being oxidized in a manner that permits a physical change of the substrate to be observed.
International Patent publication of Sep. 29, 2005, No. WO 2005/089058 of Amisar is directed to a method and kit for detecting explosive substances containing chlorate, bromate and/or organic peroxide. The suspect substance is contacted with a strongly acid solution of at least one primary or secondary aromatic amine. A chlorate or bromate type of explosive provides a distinct coloration. In the absence of such coloration, the same sample is contacted with a solution comprising cations of at least one transition metal. Organic peroxide in the sample, which was at least partially hydrolyzed by the strong acid, affords a distinct coloration.
WO 99/43846 sets forth a method and kit for detecting an organic peroxide-based explosive in a sample. The sample is dissolved in a suitable organic solvent and then hydrolyzed with a strong acid to release hydrogen peroxide, which is then detected in a known manner.
U.S. Pat. No. 7,829,020 of Jul. 31, 2008 to Pagoria et al. discloses a field-portable colorimetric detection device for organic peroxides and hydrogen peroxides. It utilizes a swipe material attached to a polyethylene tube containing two crushable vials containing components of a colorimetric detection reagent, separated into dry and liquid ingredients. After swiping a suspected substance or surface the vials are broken, the ingredients are is mixed thoroughly, and the reagent is allowed to wick into the swipe material. The presence of organic peroxides or hydrogen peroxide is confirmed by a deep blue color. The colorimetric reagent components have to remain separated before a test is performed because of high instability. When mixed together they themselves can develop a blue color (false positive blank) after about a week.